Tuesday, March 5, 2013
Poles and Jews along the Middle East to North Europe cline of genetic diversity
The figures below come from a recent study on the genetic substructures of population isolates in Northeastern Italy by Esko et al. They show the results of ADMIXTURE and PCA cluster analyses of a wide variety of groups from Europe and the Middle East, and I think very succinctly illustrate where these samples fall along the cline of genetic diversity that runs from the Middle East to North Europe.
One of the most striking things about the results is the difference between the Ashkenazy sample and their gentile European hosts from Poland, Germany and Austria. The gentiles cluster with Northern European populations, while the Ashkenazy Jews appear very similar to their religious kin, the Sephardic Jews. This probably suggests that both Ashkenazy and Sephardic Jews descend from the same ancestral group, and perhaps also that they've kept in regular contact since becoming separate ethnic entities.
The Ashkenazy Jews do appear to carry some Central and/or Eastern European admixture, and this is found at clearly elevated levels in a few of the Ashkenazy individuals. However, overall this influence has not been strong enough to differentiate the Ashkenazy from Sephardic Jews in a significant way in terms of West Eurasian genetic variation.
Esko et al., Genetic characterization of northeastern Italian population isolates in the context of broader European genetic diversity, European Journal of Human Genetics advance online publication 19 December 2012; doi: 10.1038/ejhg.2012.229